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A three-dimensional operational hydrodynamic model, developed at the Institute of Oceanography, University of Gdańsk was used to forecast hydrological conditions in the Oder Estuary. The model was based on the coastal ocean circulation model known as the Princeton Ocean Model (POM). Because of wind-driven water backup in the Oder mouth, a simplified operational model of river discharge, based on water budget in a stream channel, was developed. Linking these two models into a single system made it possible to forecast water levels, currents, water temperature, and salinity in the estuary. A good fit between the observed and computed data allowed to consider the model as a reliable environmental tool. Obtaining a hydrological forecast via a quick website access gives potential users an opportunity to predict the day-by-day course of processes that may affect different areas of human life and activities, e.g., navigation, port operations, flood protection of coastal areas; the predictions may also be used in studies of coastal processes in the estuary.  相似文献   
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《Cell reports》2020,30(3):642-657.e6
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《Cell reports》2020,30(4):1152-1163.e4
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Sedimentological connectivity is an important issue in soil erosion and sediment transport. Landscape patterns, in combination with the rainfall regime, are known to shape such sedimentological connectivity. The quantification of sedimentological connectivity provides a link between sediment delivery and landscape pattern. There are two categories of connectivity: structural connectivity, which describes the physical coupling of landscape units, and functional connectivity, which delineates the linkage among landscape elements maintained by material transport. To quantify sedimentological connectivity, both the physical coupling of, and material transfer between, the various landscape components need to be assessed. This study quantifies the sedimentological connectivity of a headwater catchment in the Loess Plateau of China using the soil erosion and sediment delivery model (WATEM/SEDEM). Based on the model, two indicators of connectivity were developed: the area of sedimentologically effective catchment area (SEA) that contributes sediment to the sinks, and the minimum sediment output of locations on the flow path that link sources and sinks. This approach effectively represents the annual status of catchment-scale sedimentological connectivity and, furthermore, the simple structure and readily available input data make it highly practicable. However, for larger river systems in which sediment transport between sources and sinks occur over longer time scales and larger spatial scales, we suggest different techniques for quantifying the sediment flux and parameters delineating the physical coupling of landscape units.  相似文献   
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The relative importance of multiple vectors to the initial establishment, spread and population dynamics of invasive species remains poorly understood. This study used molecular methods to clarify the roles of commercial shipping and recreational boating in the invasion by the cosmopolitan tunicate, Botryllus schlosseri. We evaluated (i) single vs. multiple introduction scenarios, (ii) the relative importance of shipping and boating to primary introductions, (iii) the interaction between these vectors for spread (i.e. the presence of a shipping-boating network) and (iv) the role of boating in determining population similarity. Tunicates were sampled from 26 populations along the Nova Scotia, Canada, coast that were exposed to either shipping (i.e. ports) or boating (i.e. marinas) activities. A total of 874 individuals (c. 30 per population) from five ports and 21 marinas was collected and analysed using both mitochondrial cytochrome c oxidase subunit I gene (COI) and 10 nuclear microsatellite markers. The geographical location of multiple hotspot populations indicates that multiple invasions have occurred in Nova Scotia. A loss of genetic diversity from port to marina populations suggests a stronger influence of ships than recreational boats on primary coastal introductions. Population genetic similarity analysis reveals a dependence of marina populations on those that had been previously established in ports. Empirical data on marina connectivity because of boating better explains patterns in population similarities than does natural spread. We conclude that frequent primary introductions arise by ships and that secondary spread occurs gradually thereafter around individual ports, facilitated by recreational boating.  相似文献   
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The hydrology of the Loosdrecht lakes area   总被引:5,自引:5,他引:0  
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成文青  陶宇  吴未  欧维新 《生态学报》2020,40(5):1789-1798
随着城市化进程的加快,对生态保护空间(Ecological Protect Area,EPA)进行优先级识别已经成为保护生物多样性,缓解城市生态压力,提高土地利用效率的重要方法之一。以苏锡常地区为例,通过形态空间格局分析(Morphological Spatial Pattern Analysis,MSPA)确定EPA,进而采用景观连接度方法对其优先级进行识别,以优先级较高的林地和水域为"源地",构建EPA网络;同时由于景观连接度方法在识别优先级时,未能体现EPA对物种决策的非等权重影响,因此本研究引入空间句法进一步对EPA进行优先级识别。结果显示:1)苏锡常地区EPA中编号1、2的林地以及太湖的优先级最高,是区域网络的3个中心,需要优先保护;2)引入空间句法的优先级识别结果与基于景观连接度的优先级识别结果存在明显差异,后者优先级较高的8个EPA,在引入空间句法后优先级降低1—2个等级;后者优先级较低的4个EPA的优先级则上升了2个等级。同时也表明:基于连接度-空间句法的EPA优先级识别方法能够反映不同景观要素对物种决策行为的非等权重影响,强化了生态要素的空间配置的生态效应,为明确关键性生态空间,提供了有效的方法补充,对保护生物多样性和维系区域生态安全具有重要意义。  相似文献   
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卢洁  焦胜  胡加琦  蔡勇  欧林之 《生态学报》2023,43(15):6332-6344
城市化背景下人类与自然环境的矛盾呈现出多尺度、层级化特征,而传统生态网络的构建方式较少考虑不同尺度下生态要素的关系,无法从区域落实到中心城区,难以形成系统性的解决方案。研究在综合梳理各尺度生态网络构建方法的基础上,以长沙市为例,基于形态学空间格局分析(Morphological Spatial Pattern Analysis,MSPA)、景观连通性原理和生态斑块重要性评价识别生态源地,并通过多层级生态阻力面的确定,综合运用最小费用路径(Least-cost path method,LCP)、电路理论、层级传导理论、尺度嵌套等方法对市域、都市区、中心城区的生态网络进行了协同构建和层级优化,最后基于不同尺度生态网络的特点应用并落实到多层级的国土空间规划体系中。研究结果表明:(1)长沙市域生态网络和都市区生态网络具有较好的层级嵌套特征;共识别两尺度生态叠合源地14个、生态叠合廊道15条,主要通过中心城区内的湘江、浏阳河和捞刀河部分河段与外围生态绿圈相衔接,形成"外环内楔"的空间格局。(2)确定市域重要廊道、市域潜在廊道、生态叠合廊道、都市区重要廊道、都市区潜在廊道的核心保护面积共501.14 km2,并提取位于生态廊道核心保护区范围内的生态夹点和生态障碍点,以进一步落实生态保护修复策略。(3)得到具有重要生态连通功能的中心城区生态绿道长度441.2 km,生态修复单元56个,并结合生态阻力值划分为5级进行针对性修复。(4)基于不同尺度生态网络的衔接、嵌套,最终构建"市域总体生态安全格局-都市区城市生态空间发展格局-以城市绿道为基础的中心城区生态修复单元",并与不同层级的国土空间规划体系相对应。研究结果将为以大城市为中心的跨尺度生态系统修复和生态安全格局构建提供科学参考。  相似文献   
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